1-D Tire Patch Apparatus and Methodology

ABSTRACT

Disclosed is a tire mountable apparatus and method that includes a substrate defining a longitudinal direction, a top surface and a bottom surface. The substrate has a plurality of conductor terminals arranged in a substantially linear relationship. A first support element is located below the bottom surface of the substrate and a second support element is located above the top surface of the substrate. The plurality of conductor terminals are positioned between the first and second support elements. The substrate may be a piezoelectric device having a piezoelectric layer arranged between first and second conductive layers. The plurality of conductor terminals may be arranged in a substantially linear relationship along a line about  80 ° to about  100 ° to the longitudinal direction of the substrate, and the longitudinal direction of the substrate being substantially perpendicular to the direction of rotation of the tire.

FIELD OF THE INVENTION

The present subject matter relates to a tire apparatus. In particular,the present subject matter relates to apparatus having length and widthdimensions related to physical aspects associated with tires in which itmay be mounted for providing enhanced endurance of the tire apparatus.The present subject matter also relates to the use of such tireapparatus or structures to obtain enhanced operational and endurancecharacteristics for devices supported by such structures.

BACKGROUND OF THE INVENTION

The incorporation of electronic devices with tire structures has beenshown to yield many practical advantages. Tire electronics may providetheir own power source whose operation depends on tire related phenomenaand may also include sensors and other components for obtaininginformation regarding various physical parameters of a tire, such astemperature, pressure, number of tire revolutions, tire rotation speed,etc. Such information may be useful in tire monitoring and warningsystems, and may even be employed with feedback systems to monitorproper tire pressure levels.

United States Published Patent Application 2003/0209063 (Adamson et al.)is directed to a system and method for generating electric power from arotating tire's mechanical energy using piezoelectric fiber composites.

United States Published Patent Application 2003/0056351 (Wilkie et al.)is directed to a piezoelectric micro-fiber composite actuator and amethod for making the same.

U.S. Pat. No. 6,093,997 (Zimnicki et al.) is directed to a piezoelectricresonator embedded within an electrically insulating substrate assembly,such as a multilayer printed circuit board.

U.S. Pat. No. 5,747,916 (Sugimoto et al.) is directed to a piezoelectrictransformer unit which transforms an input voltage into an outputvoltage and which includes a piezoelectric transformer element driven byhigh electric power.

The disclosures of all of the foregoing United States patent andpublished patent applications are hereby fully incorporated into thisapplication for all purposes by reference thereto. While variousimplementations of piezoelectric generators have been developed, andwhile various combinations of tire characteristic monitoring deviceshave been implemented, no design has emerged that generally encompassesall of the desired characteristics as hereafter presented in accordancewith the subject technology.

SUMMARY OF THE INVENTION

In view of the recognized features encountered in the prior art andaddressed by the present subject matter, an improved tire mountableapparatus and methodology for providing enhanced endurance for tirepatches and associated supported devices and structures has beenprovided.

In one particular embodiment, a tire mountable apparatus may include asubstrate defining a longitudinal direction, a top surface and a bottomsurface. The substrate may have a plurality of conductor terminalsarranged in a substantially linear relationship. The tire mountableapparatus may include a first support element located below the bottomsurface of the substrate and a second support element located above thetop surface of the substrate. The plurality of conductor terminals maybe positioned between the first and second support elements.

In another exemplary embodiment of the present invention, a method isprovided that corresponds to positioning a first support element beneaththe bottom surface of the substrate so that the first support elementoverlaps the plurality of conductor terminals of the substrate andpositioning a second support element above the top surface of thesubstrate so that the second support element overlaps the plurality ofconductor terminals of the substrate.

Still further, it is to be understood that different embodiments, aswell as different presently preferred embodiments, of the presentsubject matter may include various combinations or configurations ofpresently disclosed features, steps, or elements, or their equivalents(including combinations of features, parts, or steps or configurationsthereof not expressly shown in the figures or stated in the detaileddescription of such figures). Additional embodiments of the presentsubject matter, not necessarily expressed in the summarized section, mayinclude and incorporate various combinations of aspects of features,components, or steps referenced in the summarized objects above, and/orother features, components, or steps as otherwise discussed in thisapplication. Those of ordinary skill in the art will better appreciatethe features and aspects of such embodiments, and others, upon review ofthe remainder of the specification.

BRIEF DESCRIPTION OF THE DRAWINGS

A full and enabling disclosure of the present invention, including thebest mode thereof, directed to one of ordinary skill in the art, is setforth in the specification, which makes reference to the appendedfigures, in which:

FIG. 1 diagrammatically illustrates a 1-D tire mountable apparatusconstructed in accordance with present technology;

FIG. 2 diagrammatically illustrates the sandwich construction of apiezoelectric generator as may be associated with a 1-D tire mountableapparatus constructed in accordance with present technology;

FIG. 3 representatively illustrates, in overlay, representations forcomparison of transverse profiles at top of rotation and center ofcontact patch of a representative tire in which the present technologymay be employed;

FIG. 4 representatively illustrates variations in the radius ofcurvature of an exemplary tire in which the present technology may beemployed;

FIG. 5 generally represents an exemplary tire and illustrates themounting position and orientation of the 1-D tire mountable apparatustherein;

FIG. 6 generally represents a cross-section of an unloaded tire inflatedat rated pressure useful in explaining the selection of the widthdimension of a substrate in accordance with present technology;

FIG. 7 graphically illustrates the relationship between the mesa heightof an elastomeric patch usable with the tire mountable apparatus of thepresent technology and the width of a substrate selected in accordancewith present technology expressed in degrees.

FIG. 8 representatively illustrates a plan view of an exemplarysubstrate in accordance with one embodiment of the present technology;

FIG. 9 representatively illustrates an exploded view of an exemplarytire mountable apparatus in accordance with one embodiment of thepresent technology; and

FIGS. 10 a-10 c representatively illustrate cross-sectional views ofexemplary tire mountable apparatus in accordance with variousembodiments of the present technology.

Repeat use of reference characters throughout the present specificationand appended drawings is intended to represent same or analogousfeatures or elements of the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Aspects of the present subject matter may be concerned with a 1-D tiremountable apparatus having a length and width related to certain aspectsof the tires in which the apparatus may be mounted. It should beappreciated in the following discussion that the term “1-D” is primarilyintended to represent that the tire mountable apparatus of the presenttechnology is so designated, not because it actually has only onedimension, but rather to emphasize the fact that the width dimension issignificantly less than the length dimension for reasons that will bemore fully explained later. Of course also, the apparatus does have aheight as the device is actually a three-dimensional object, but suchheight also, relative to the length is significantly less.

Further, it should be appreciated that, as employed later herein withrespect to certain embodiments of the present technology, the term“generator” is meant to convey that flexure of a piezoelectric device asmay be associated with the present subject matter will produce an outputvoltage across output terminals provided on the device. Further still,as the piezoelectric device associated with the present technology maybe employed as a sensor as well as a generator either separately orconcurrently, the terms generator and sensor may be used hereinafterinterchangeably.

Selected combinations of aspects of the disclosed technology correspondto a plurality of different embodiments of the present invention. Itshould be noted that each of the exemplary embodiments presented anddiscussed herein should not insinuate limitations of the present subjectmatter. Features or steps illustrated or described as part of oneembodiment may be used in combination with aspects of another embodimentto yield yet further embodiments. Additionally, certain features may beinterchanged with similar devices or features not expressly mentionedwhich perform the same or similar function.

Reference will now be made in detail to the presently preferredembodiments of the subject 1-D tire mountable apparatus and methodology.Referring now to the drawings, FIG. 1 diagrammatically illustrates 1-Dtire mountable apparatus 100 constructed in accordance with presenttechnology. As may be seen from FIG. 1, 1-D tire mountable apparatus100, of course, actually has three dimensions. In particular, asubstrate portion of apparatus 100 which may be configured as a sandwichstructure 102 is constructed as indicated in FIG. 1 as having a length Land width W. Further, the width dimension W is significantly less thanthe length L. In preferred embodiments, L is at least twice W.

Also illustrated as an optional portion of tire mountable apparatus 100is an elastomeric patch 108 that has a top surface 114 and a lowersurface 104 separated by a mesa 106 having a height H. In accordancewith present technology the height H is less than either the width W orlength L.

With brief reference to FIG. 4, those of ordinary skill in the art willappreciate that a tire operating under rated pressure and rated loadwill have a profile similar to that illustrated in FIG. 4. This profileincludes a generally flat area normally described as the contact patchwith curved portions on either side of the contact patch. Further, thereare transition areas immediately preceding and following the contactpatch where the radius of curvature of a tire operating under ratedpressure and rated load changes from a substantially constant radius toa generally flat or infinite radius. As will be explained furtherhereinafter, the width W of tire mountable apparatus 100 is selected tofall within these transition areas. More particularly, the width W isselected to fall within a somewhat narrower width as will be more fullyexplained later with respect to FIG. 6.

As will be explained further later, the device of the present technologyis referred to herein as a “1-D” device based generally on the conceptthat the present technology has provided a device that, when including apiezoelectric device, provides for the generation of an output signalhaving substantial energy for harvesting as a result of strain appliedprincipally from only one dimension, i.e., the relatively longer lengthdimension of the device. Conversely, strain applied from the shorterdimension, the width W of the device, provides less signal productionthan that along the longer length dimension, but may still provide asignal opportunity if interpreted correctly. Further, when employed as asupport structure for printed circuit board mounted electronics, the 1-Dtire mountable apparatus provides a substantially strain free mountingarrangement for such printed circuit boards. These concepts will be morefully explained with reference to FIGS. 3 and 4 herein after.

With further reference to FIG. 1, it will be seen that 1-D tiremountable apparatus 100 corresponds, in one embodiment, to an optionalelastomeric patch having a substrate that may correspond to a sandwichstructure 102. Sandwich structure 102, in an exemplary embodiment maycorrespond to a layer of piezoelectric material, conductive layers andat least one support layer as will be explained more fully with respectto FIG. 2 that may function as a sensor or voltage generators.

A substrate in accordance with present technology, possibly in the foamof sandwich structure 102, may be supported on an optional layer ofelastomeric material 108 to form a patch that may be secured to theinner liner of a tire using standard tire patch repair methodologies.Elastomeric material 108 may be formed as a lower surface 104 and acentrally located raised mesa portion 106 having a top surface 114 onwhich sandwich structure 102 may be secured. In general, the elastomericmaterial may correspond to a material composition normally employed as asidewall material in the construction of pneumatic tires. As those ofordinary skill in the art will appreciate, such material is a generallyoxidation-resistant compound.

In an exemplary embodiment of the present subject matter, a tire patchassembly may be produced by coating an adhesive on a portion of sandwichstructure 102, placing the structure in a specially designed moldconfigured to accommodate sandwich structure 102, filling the remainderof the mold with an elastomeric material and curing the patch. A patchso formed may then be secured to the inner liner of a tire usingstandard tire patch repair methods. In an exemplary configuration, theadhesive may be Chemlok® available from LORD Corporation and theelastomeric material may correspond to rubber.

In accordance with another exemplary embodiment of the present subjectmatter, it is possible to secure sandwich structure 102 directly to theinner liner of a tire using Chemlok® alone without the intermediary useof the elastomeric material. It should also be appreciated that a tiremountable apparatus constructed in accordance with present technologymay be similarly mounted to a non-pneumatic tire and wheel combinationknown as a Tweel® non-pneumatic tire, manufactured by the owner of thepresent technology.

With brief reference now to FIG. 2, there is illustrated an exemplarysandwich structure 200, corresponding to sandwich structure 102 ofFIG. 1. Sandwich structure 200 corresponds to a layer of piezoelectricmaterial 202 with a first layer of conductive material 204 on one sidethereof and a second layer of conductive material 204′ on a second sidethereof The first layer of conductive material 204 is secured to a layerof insulating material 206 that acts as a supporting substrate for thesandwich structure 200. In exemplary embodiments of the present subjectmatter, piezoelectric material 202 may correspond to lead zirconiumtitanate (PZT), conductive materials 204, 204′ may comprise copperlayers, and insulating material 206 may correspond to a fire resistantsubstrate material commonly called FR4.

In another exemplary embodiment of the present subject matter, anoptional second layer of insulating material 206′ may be secured toconductive layer 204′. Such a second layer of insulating material, ifprovided, may also be FR4.

With further reference to FIG. 1, a pair of connection/support terminalsor posts 110, 112 is positioned along line 132 and on either side ofcentral line 134. Terminal 110 may be electrically coupled to conductivelayer 204 while terminal 112 may be electrically coupled to conductivelayer 204′. It should be appreciated by those of ordinary skill in theart that the connection/support terminal configurations described areexemplary only as other configurations are possible and are alsocontemplated by the present technology. For example, while the presentdisclosure generally illustrates a sandwich structure 102 substantiallycompletely covering and even, optionally, partially overhanging the topsurface 114 of patch 108, such are not specific limitations of thepresent technology as sandwich structure 102 may actually be sub-dividedinto two or more portions. Further, while a pair of connection/supportterminals 110, 112 are illustrated, there may be provided additionalsuch connection/support terminals positioned along a common line withconnection/support terminals 110, 112 or along parallel lines asillustrated at 110′, 112′ and 110″, 112″. Further still, in embodimentswhere sandwich structure 102 may be sub-divided into two or moreportions, such portions may be electrically connected in parallel by wayof connection/support terminals 110, 112 or in other electricalconfigurations as desired including serially or individually byproviding additional connection/support terminals.

A significant aspect of the present disclosure is that the pair ofconnection/support terminals 110, 112 is positioned along line 132, or,more generally, along a line perpendicular to central line 134, wherecentral line 134 is along the primary bending direction 130 of the 1-Dtire mountable apparatus 100. In accordance with present technology,lines 132 and 134 may vary from true perpendicular (i.e. 90°) alignmentby ±10, ±5, or ±2 degrees. As will be made clear later, line 132 may besaid to identify the direction of rotation of a tire in which a tiremountable apparatus constructed in accordance with the presenttechnology is to be mounted. In general, because the primary bendingdirection 130 is along central line 134, line 132 and hence the mountingposition for pair of connection/support terminals 110, 112 may bepositioned anywhere along central line 134, however the preferredposition is generally at a more central location as illustrated.

As will be explained further later, when 1-D tire mountable apparatus100 is positioned in a tire in accordance with present technology, aprimary bending direction as illustrated by double-arrowed line 130 isestablished due to the positioning of the 1-D tire mountable apparatus100 in the tire as well as the length L and width W of the 1-D tiremountable apparatus 100.

With bending limited to along this one dimension, i.e. the 1-Ddirection, strain at and between connections to devices mounted toconnection/support terminals 110, 112 and alternately or in additionconnection/support terminals 110′, 112′ and 110″, 112″, is minimized dueto their perpendicular alignment to the primary strain direction, i.e.the 1-D orthogonal connection line 132. If, for example, on the otherhand, connection/support terminals 110, 112 were to be positioned alongcentral line 134, the primary bending line, separation distances betweenconnection/support terminals 110, 112 would change with any bendingalong central line 134. Such would place a significant strain on anydevice or printed circuit board 136 (illustrated in phantom in FIG. 1)and alternately or in addition circuit boards 136′, 136″ as may bemounted to connection/support terminals 110, 112 and/orconnection/support terminals 110′, 112′ and/or 110″, 112″. It should beappreciated that any printed circuit board 136, 136′, 136″ mounted totheir corresponding connection/support terminals may be mounted in sucha manner that the connection/support terminals provide all of thesupport for the printed circuit board. That is, the printed circuitboards may be mounted such that they are not supported by contact withany underlying structure other than the connection/support terminals.

In certain exemplary embodiments of the present invention, the multiplecircuit boards 136, 136′, 136″ are not physically coupled together totake advantage of the perpendicular to the primary strain directionorientation of the support terminals. In a particular embodiment, noadditional pins are provided in parallel line alignment with thealignment line of the pair of support terminals 110, 112 and coupled tothe same printed circuit board. Additional support terminals may,however, be placed along the same line with support terminals 110, 112.

With brief reference to FIG. 5, there is generally illustrated a tire500 having a tread portion 510 and sidewall portions 520, 522. Inaccordance with present technology, 1-D tire mountable apparatus 100 ismounted laterally between sidewall portions 520, 522 in the centralportion of tire summit 530. As may be seen in FIG. 5, 1-D tire mountableapparatus 100 may be mounted on the inner liner of tire 500 orientedsuch that the length dimension L extends in the direction of sidewalls520, 522, i.e., is aligned substantially laterally to the direction ofrotation of tire 500. Stated differently, the patch pose angle of the1-D tire mountable apparatus is such that the dimension L is alignedsubstantially 90° to the direction of rotation of tire 500. It should beappreciated that in the present context, the phrase “alignedsubstantially” in a particular direction is intended to signify thatthere may be a variation in alignment from a perfect alignment in therange from about ±0° to about ±20°, such as ±5° to about ±15°, such asabout ±8° to ±12°, such as about ±10°, such as about ±5°, or about ±4°,or about ±3°, or about ±1° or any other variation in alignment or rangeof variation in alignment therebetween.

Using the teachings disclosed herein, those of ordinary skill in the artshould appreciate that certain embodiments of the present invention maynot be limited to any particular orientation of the tire mountableapparatus 100. For example, in certain embodiments, the tire mountableapparatus 100 may be mounted closer to, or even directly on, sidewallportions 520 or 522 of the tire. In these embodiments, the lengthdimension of the tire mountable apparatus 100 may be aligned in anydirection.

In exemplary configurations, the length dimension may be chosen suchthat tire mountable apparatus 100 lies in the central portion of thetire summit and extends over a significant portion of that area of abelted tire construction where the space separating the various belts isconstant. Of course, as previously mentioned, tire mountable apparatus100 may also be similarly mounted in a non-pneumatic wheel and tire suchas the Tweel® non-pneumatic tire.

Based on the lateral orientation and the fact that the width dimensionis relatively insignificant at least with respect to any bending orgeneration of strain from variations based on the rolling direction ofthe tire, 1-D tire mountable apparatus 100 sees primarily a monotonicradius change based on the tire's transverse profile changes withrotation.

This later profile change concept may best be understood from a study ofFIGS. 3 and 4. FIG. 3 representatively illustrates, in overlay,representations for comparison of transverse profiles at top of rotationand center of contact patch of a representative tire in which thepresent technology may be employed and illustrates in phantom themounting orientation of tire mountable apparatus 100. FIG. 4representatively illustrates variations in the radius of curvature of anexemplary tire in which the present technology may be employed. Asgenerally represented in FIG. 3, for an exemplary normally inflated275/80R22.5 tire, the transverse radius of curvature or profile (p)changes from p-500 mm with the tire at the top of its rotation top--flat, i.e., a substantially infinite radius of curvature, at thecenter of the contact patch. Those of ordinary skill in the art willappreciate that the “contact patch” corresponds to the surface area ofthe tire in “contact” with the travel surface and that such surface issubstantially “flat” over a generally smooth surface.

FIG. 4, on the other hand, illustrates that the circumferential radiusof curvature (R) will vary between a substantially constant non-contactpatch area, i.e., a substantially un-deflected portion of the tire, anda significantly higher radius of curvature within the contact patchduring tire rotation and will produce two curvature peaks at entry andexit of the contact patch that increase with deflection. In accordancewith present technology, 1-D tire mountable apparatus 100, due to theselection of width and the lengthwise mounting orientation in a tire,sees primarily a monotonic radius change from, for example, about 500 mmto flat, thereby avoiding two deflection-dependent circumferentialpeaks.

Exposure to primarily a monotonic radius change is one of the featuresof the present technology that results in enhanced endurance of thesubject 1-D tire mountable apparatus. A second feature resulting from1-D width selection, when a piezoelectric generator/sensor is associatedwith the tire mountable apparatus, is the substantial elimination ofextraneous signal generation from longitudinal strain resulting frompassage of the piezoelectric device-associated tire mountable apparatusthrough the entry and exit points to the tire contact patch. Suchinherent signal filtering contributes to greater accuracy of signalprocessing for the various uses to which such signals may be placedwithin any particular usage environment.

With attention directed now to FIG. 6 it will be seen that the width Wof the substrate portion of the tire mountable apparatus of the presentsubject matter may be selected by taking into consideration physicalparameters of a tire at rated inflation pressure and under no loadconditions. Such a tire is illustrated as tire 600 and has a uniformdiameter D. Tire 600 has a radius r extending from a central rotationalpoint 602 to the inner surface 608 of tire 600. Lines 604 and 606extending from the central rotational point 602 to inner surface 608establish an angle θ that, in accordance with technology is selected tobe in the range of about 1° to about 5°, such as about 2° to about 4°,such as about 3°, or about 2°, or about 1° or any other angle or rangeof angles therebetween. Stated differently, the length of arc subtendedalong the inner surface 608 of tire 600 corresponds to about 1° to about5° of rotation measured from line 604 extending from the center ofrotation 602 to the inner surface 608 of the unloaded tire 600 when itis inflated to rated pressure. This length of arc established themaximum width W of the substrate.

By selecting the width W of 1-D tire mountable apparatus 100 to benarrow enough to substantially avoid strain from entry into and exitfrom the contact patch area, a number of benefits are obtained. As aninitial benefit, strain on the 1-D tire mountable apparatus 100 per seis effectively limited to one direction thereby offering potential forprolonged life expectancy. In an exemplary configuration, for example inthe previously noted exemplary 275/80R22.5 tire, width W may be selectedto be less than about 30 mm. In any event, the width W should be limitedto a dimension fitting within a tire inner surface dimension asdescribed with relation to FIG. 6.

As previously referred to herein above, as tire 400, operating at ratedpressure and rated load, rotates in the direction of arrow 418, twotransition zones are created as the tire tread goes into and out ofcontact with the surface over which the tire is traveling. In the FIG. 4example, the contact patch exit portion is identified as a transitionportion or zone between lines 412, 414. A similar transition portion is,of course, formed at the entrance to the contact patch portion but hasnot been separately illustrated herein. As illustrated, the width W oftire mountable apparatus 100 is selected to fit entirely within thistransition portion or zone so as to substantially avoid flexing of tiremountable apparatus 100 during passage through the transition portion.This leads to a second benefit, which is that generation of extraneousvoltage signals from a mounted piezoelectric device from potentialbending in a second direction is minimized.

Finally, by reducing the overall width, a more stable mountingorientation for terminal/support elements 110, 112 arranged in a lineperpendicular to the primary strain direction is provided that reducesstrain on mechanical and electrical coupling to devices and/or printedcircuit boards as may be mounted thereon. In an exemplary configuration,the spacing between terminal/support elements 110, 112 may be selectedto be less than about 18 mm.

With respect to overall length dimension determination, it will beappreciated from the previous discussion that the length L of 1-D tiremountable apparatus 100, that is, the lateral dimension with respect toa tire, should be minimized for endurance and maximized for energygeneration. By orienting the mountable apparatus length laterally in thesummit center, a structure is provided that very effectively increasesdevice endurance while providing a device that is insensitive to tiredeflection. As has been previously noted, the length L may be chosensuch that tire mountable apparatus 100 lies in the tire summit betweenthe shoulders and may extend over a significant portion of that area ofa belted tire construction where the space separating the various beltsis constant. In an exemplary configuration, the length L may be chosento be at least twice the width W. In an exemplary configuration, it hasbeen found experimentally that a 10× order of improvement to thedistance to fatigue crack onset may be obtained by selecting suchmounting orientation and length and width relationships.

With reference now to FIG. 7, there is illustrated a relationshipbetween the height H of optional elastomeric patch 108's mesa 106. Thegraph illustrates that the maximum width W_(max) in terms of degrees isrelated to the height H of the mesa as a linear function up to a maximummesa height H of 5 mm. In the instance that no elastomeric patch isemployed, that is the substrate is adhered directly to the inner linerof the tire, W_(max) is selected to be 1°. As the height H increases,W_(max) increases linearly to a maximum of 5°. Generally thisrelationship may be defined as W_(max)=(4/5)H+1 for 0<H≦5. In allcircumstances, however, the relationship L>W>H should be respected.Those of ordinary skill in the art will appreciate that the elastomericpatch, if present, provides a degree of isolation between the tire andthe mounted apparatus 100. In the case of a piezoelectricsensor/generator being included, an increasing height H will produce areduction in strain in the length L direction of the device. This, inturn, will produce less voltage generation from the piezoelectric devicebut will provide an increase in structural reliability so that a designbalance should be taken into consideration in selecting the mesa heightversus the length L whose selection determines the amount of voltagegenerated. In any event, the length L should not be so long as to causethe device to extend into the shoulder portion of the tire. The shoulderportion is understood to be that portion of the tire beyond the summitwhere the spacing of belt layers in a belted tire is no longersubstantially constant when moving from the central portion of thesummit toward the sidewalls.

Referring now to FIGS. 8-10, additional exemplary embodiments of a tiremountable apparatus according to the present technology will bediscussed in detail. FIG. 8 depicts a plan view of an exemplarysubstrate 800 having a length L for use in a tire mountable apparatus.The length L of the substrate defines the longitudinal direction of thesubstrate. The substrate 800 may correspond to sandwich structure 200 asshown in FIG. 2 having a layer of piezoelectric material 202 with afirst layer of conductive material 204 on one side thereof and a secondlayer of conductive material 204′ on a second side thereof. The firstlayer of conductive material 204 is secured to a layer of insulatingmaterial 206 that acts as a supporting substrate for the sandwichstructure 200. As set forth above, in certain embodiments, thepiezoelectric material 202 may correspond to lead zirconium titanate(PZT), conductive materials 204, 204′ may comprise copper layers, andinsulating material 206 may correspond to a fire resistant substratematerial commonly called FR4.

The substrate 800 may include a first piezoelectric device 810 and asecond piezoelectric device 820. In one embodiment, first piezoelectricdevice 810 may correspond to a power piezoelectric generator whilesecond piezoelectric device 820 may correspond to a signal piezoelectricgenerator. The power piezoelectric device 810 may be configured toprovide power to various devices in the tire mountable apparatus and thesignal piezoelectric device 820 may be configured to provide an isolatedpiezoelectric signal that is used for analytical purposes.

Substrate 800 includes a plurality of conductor terminals 840, 842, 844,and 846 on the substrate. Although only four conductor terminals 840,842, 844, and 846 are illustrated in FIG. 8, using the teachingsdisclosed herein, those of ordinary skill in the art should understandthat the present invention is not limited to any particular number ofconductor terminals. For instance, the present technology may encompasstwo conductor terminals, four conductor terminals, six conductorterminals, five conductor terminals or any other number of conductorterminals.

The plurality of conductor terminals shown in FIG. 8 include a pair ofouter conductor terminals 840, 842 and a pair of inner conductorterminals 844, 846. Conductor terminals 840, 842, 844, and 846 may beused to provide an electrical connection to first and secondpiezoelectric devices 810, 820 embedded in the substrate. For instance,the pair of outer conductor terminals 840, 842 may provide an electricalconnection to first piezoelectric device 810 through conductive vias850. The pair of inner conductor terminals 844, 846 may provide anelectrical connection to second piezoelectric device 820 throughconductive vias 850. Alternatively, the first piezoelectric device 810may be operably connected to terminals 840 and 844 while the secondpiezoelectric device 820 may be operably connected to the other outerconductor terminal 842 and inner conductor terminal 846. Those ofordinary skill in the art should readily understand that thepiezoelectric devices 810, 820 of the substrate 800 may be connected toany particular conductor terminal or combination of conductor terminalswithout deviating from the scope of the present invention.

Conductor terminals 840, 842, 844, and 846 may be any structure that canbe used to establish an electrical connection between piezoelectricdevices 810, 820 or conductive layers embedded in the substrate andvarious other devices or structures in the tire mountable apparatus. Forexample, conductor terminals 840, 842, 844, and 846 may be in the formof a conductive annulus, such as a copper annulus, that surrounds anopening adapted to receive an electrical connector or post. Theconductive annulus may be operably connected to an electrical connector,post or other structure by threading the electrical connector, post orother structure through the opening in the conductive annulus. Theconductive annulus will surround and be in contact with the electricalconnector, post or other structure, establishing any necessaryelectrical connection. In particular embodiments, conductor terminals844 and 846 may be in the form of conductive buttons, such as copperbuttons. The conductive buttons provide an exposed conductive surfacefor electrical contact with an electrical connector or other structure.

In accordance with the present technology, conductor terminals 840, 842,844, and 846 are arranged on the substrate 800 in a substantially linearrelationship along line A-A. It should be appreciated that in thepresent context, use of the phrase “substantially linear relationship”is intended to signify that there may be a variation in alignment from aperfect linear relationship in the range from about ±0° to about ±20°,such as about ±5° to about ±15°, such as about ±8° to about ±12°, suchas about ±10°, such as about ±5°, or about ±4°, or about ±3°, or about±1° or any other variation in alignment or range of variation inalignment therebetween.

The conductor terminals 840, 842, 844, and 846 should be substantiallyaligned long line A-A, which is along a line about 80° to about 100° tothe longitudinal direction of the substrate. The longitudinal directionof the substrate may be aligned substantially perpendicular to thedirection of rotation of a supporting tire. Using the teachingsdisclosed herein, those of ordinary skill in the art should appreciatethat the substrate 800 may have any number of lines of conductorterminals for attachment to a printed circuit board. For example, asubstrate may have two lines of conductor teiminals, three lines ofconductor terminals, or any other number of conductor terminals.

As explained in detail above, when the 1-D substrate 800 is positionedin a tire in accordance with the present technology, bending of thesubstrate is limited to one dimension, i.e. the 1-D direction. Arrangingthe conductor terminals 842, 846 in a substantially linear relationshipalong line A-A minimizes strain at and between connections to devicesconnected to the conductor terminals 840, 842, 844, and 846 due to theirperpendicular alignment to the primary strain direction. If, forexample, on the other hand, the plurality of conductor terminals were tobe along the primary bending line, separation distances between theconductor terminals would change with any bending along the primarybending line. Such would place a significant strain on any device orprinted circuit board connected to the conductor terminals 840, 842,844, and 846.

Referring now to FIG. 9, exemplary tire mountable apparatus 900 will bedescribed in detail. As illustrated, exemplary tire mountable apparatus900 includes a layer of elastomeric material 910, first support element920, substrate 800, second support element 930, and printed circuitboard 940. Substrate 800, which may be in the form of sandwich structureas shown in FIG. 2, may be supported on layer of elastomeric material910 to foim a patch that may be secured to the inner liner of a tireusing standard tire patch repair methodologies. Elastomeric material 910may be formed as a base portion 912 and a centrally located raised mesaportion 914 on which substrate 800 may be secured. As set forth above,the elastomeric material may correspond to a material compositionnormally employed as a sidewall material in the construction ofpneumatic tires. Of course, tire mountable apparatus 900 may also besimilarly mounted in a non-pneumatic wheel and tire such as the Tweel®non-pneumatic tire.

Embedded within optional layer of elastomeric material 910 is firstsupport element 920. First support element 920 should have a degree ofrigidity so as to provide mechanical support and protection for theconductor terminals 840, 842, 844, and 846 on the substrate as well asto provide mechanical support for other components of the tire mountableapparatus 900. The first support element 920 may be composed of anyinsulating or non-conductive material, such as, for example, FR4. Asused herein, use of phrases like “insulating” or “non-conductive”material is intended to signify any material that is at least partiallyresistive to the flow of electric current or electrons through thematerial. The first support element 920 may be bonded to the optionallayer of elastomeric material 910 through an adhesive such as Chemlok®available from LORD Corporation. In another embodiment, the firstsupport element may be formed of a hard rubber or other rigid materialthat is embedded, integral, or a part of the optional layer ofelastomeric material 910. In this embodiment, no adhesive is necessaryto bond the first support element 920 to the optional layer ofelastomeric material. The first support element 920 may also includerounded edges so as to minimize strain applied to the layer ofelastomeric material 910.

As illustrated in FIG. 9, the first support element 920 is positioned sothat it overlaps the plurality of conductor terminals 840, 842, 844, and846 arranged on the substrate 800. In the present context, use of thephrase “overlaps the plurality of conductor terminals” is intended toinclude extending over or covering the conductor terminals either aboveor below the conductor terminals. In this manner the first supportelement 920 provides protection and support for the plurality ofconductor terminals 840, 842, 844, and 846. First support element 920may include a plurality of openings or other structures that may be usedto establish an electrical connection between the printed circuit board940 and the substrate 800. In certain embodiments, the first supportelement 920 has a width that is slightly larger than the width of theconductor terminals 840, 842, 844, and 846 to ensure complete overlap ofthe conductor terminals 840, 842, 844, and 846. However, the width ofthe first support element 920 should be minimized to avoid creating alarge stress footprint on the printed circuit board 940 and so thatmechanical stresses are dispersed onto different portions of thesubstrate 800. For instance, in particular embodiments having conductorterminals with maximum diameters of about 5.5 mm to about 6 mm, thefirst support element 920 may have a width of about 7.25 mm, withvariances in this width being in the range of about ±0% to about ±20%,such as ±5% to about ±15%, such as about ±8% to ±12%, such as about±10%, or about ±5%, or about ±4%, or about ±3%, or about ±1% or anyother variation in width or range of variation in width therebetween.

Located above the substrate 800 is second support element 930. Thesecond support element 930 acts as a spacer between the printed circuitboard 940 and the substrate 800. The second support element 930 may havea height sufficient to prevent the printed circuit board 940 fromcontacting the substrate 800 when subject to mechanical stresses, suchas, for example, during rotation of a tire. Second support element 930may include a plurality of openings 935 that may be used for passage ofvarious electrical connectors from the printed circuit board 940 to thesubstrate. Second support element 930, similar to first support element920, may be formed of an insulating material, such as, for example, FR4.The second support element 930 works with the first support element 920to provide mechanical support and protection for the plurality ofconductor terminals 840, 842, 844, and 846. As illustrated, secondsupport element 930 is positioned so that it overlaps the plurality ofconductor terminals 840, 842, 844, and 846. The second support element930 preferably has a width that is smaller than the width of the firstsupport element 920 so that the stress line or footprint of secondsupport element 930 and first support element 920 relative to theprinted circuit board 940 is minimized. For instance, in particularembodiments wherein the first support element 920 has a width of about7.25 mm, the second support element preferably has a width of about 6.25mm, with variances in this width being in the range of about ±0% toabout ±20%, such as ±5% to about ±15%, such as about ±8% to ±12%, suchas about ±10%, or about ±5%, or about ±4%, or about ±3%, or about ±1% orany other variation in width or range of variation in widththerebetween.

In the tire mountable apparatus 900, the plurality of conductorterminals 840, 842, 844, and 846 is positioned between the secondsupport element 930 and the first support element 920. This structureprovides the tire mountable apparatus enhanced operational and endurancecharacteristics. For instance, the second support element and firstsupport element structure mechanically clamps the line of conductorterminals 840, 842, 844, and 846, reducing strain that may be applied tothe conductor terminals. The second support element and first supportelement structure also helps preserve good electrical contact betweenconductors or piezoelectric devices embedded in the substrate 800 andthe conductor teiminals 840, 842, 844, and 846.

In particular embodiments, the tire apparatus may comprise solder in theinterface between the first support element 920, the second supportelement 930, and/or the conductor terminals 840, 842, 844, and 846. Thesolder serves to provide corrosive protection and electrical for theplurality of conductor terminals 840, 842, 844, and 846 and to providefurther protection for the interface between the first support element920, the second support element 930, and/or the conductor terminals 840,842, 844, and 846. The solder and the interface between the firstsupport element 920, the second support element 930, and the conductorterminals 840, 842, 844, and 846 are provided further mechanicalprotection by a compression load applied to the first support element920 and the second support element 930. This compression load may beprovided by the fastening and tightening of printed circuit board 940 toposts 925.

As illustrated in FIG. 9, first support element 920 includes a pair ofposts 925 that extend from the first support element 920. The posts 925may be attached to the first support element 920 through nuts or sockets922 embedded in the first support element 920. The posts 925 should beformed from a conductive material so that the posts may be used toestablish an electrical connection between the printed circuit board 940and the substrate 800. As illustrated in FIGS. 9 and 10 a-10 c, theposts 925 may extend through the pair of outer conductor terminals 840and 842. In a particular embodiment, the posts 925 may be used toestablish an electrical connection between the power piezoelectricdevice 810, which is connected to conductor terminals 840 and 842, witha printed circuit board 940. Conductor terminals 840 and 842 may be inthe form of conductive annulus that surrounds and are contacts with theposts 925 so that any necessary electrical connection is established.

As illustrated, posts 925 extend through openings 935 in the secondsupport element and are electrically and mechanically connected to theprinted circuit board 940. Fasteners 926 may be used to mechanicallyconnect the printed circuit board 940 to the posts 925. It should beappreciated that any printed circuit board 940 mounted to thecorresponding posts 925 may be mounted in such a manner that the posts925 provide all of the support for the printed circuit board. That is,the printed circuit boards may be mounted such that they are notsupported by contact with any underlying structure other than the posts925 and incident contact with the underlying second support element 930.

The tire mountable apparatus 900 may include one or more electricalconnectors 950 configured to establish an electrical connection betweenthe printed circuit board 940 and the substrate 800. These electricalconnectors 950 are used for electrical connection only. Unlike the posts925, the electrical connectors 950 do not provide any mechanical supportfor the tire mountable apparatus. Electrical connectors 950 may be anydevice or structure that establishes an electrical connection betweenthe printed circuit board 940 and the substrate 800.

FIGS. 10 a-10 c provide a cross sectional view of the tire mountableapparatus 900 taken along the line of conductor terminals 840, 842, 844,and 846 of the substrate 800. As shown, the tire mountable apparatusincludes the first support element 920, substrate 800, second supportelement 930 and printed circuit board 940. The substrate 800 is depictedas a layer of insulating material 860, a conductive layer 870, andanother layer of insulating material 880. The conductive layer 870 mayjust be a single conductive layer embedded in the substrate, or it maycorrespond to the sandwich structure illustrated in FIG. 2, where twoconductive layers 204 and 204′ sandwich piezoelectric layer 202.

FIGS. 10 a-10 c illustrate that a plurality of different types ofelectrical connectors 950 may be used in accordance with the presenttechnology. In FIG. 10 a, the electrical connector 950 comprises asurface mount pin 950 that is operably connected to one of the innerconductor terminals 844, 846. In this embodiment, the inner conductorterminals 844, 846 may be in the form of conductive buttons that exposea conductive surface. The surface mount pin 950 is operably connected tothe exposed conductive surface of the conductor terminal 844, 846. Thesurface mount pin 950 is also received into socket 942 on the printedcircuit board 940, establishing the electrical connection between theinner conductor terminals 844 and 846 and the printed circuit board 940.

Another exemplary embodiment of an electrical connector 950 isillustrated in FIG. 10 b. In this exemplary embodiment, the electricalconnector 950 comprises a spring pin that is operably connected to theprinted circuit board 940. Spring pin 950 may be compressed onto one ofthe inner conductor terminals 844, 846 to establish the electricalconnection. For instance, the inner conductor terminals 844 and 846 maybe in the form of conductive buttons that expose a conductive surface.When the printed circuit board 940 is mounted to the tire mountableapparatus 900, spring pin 950 may be compressed through the secondsupport element 930 and onto the exposed conductive surface of the innerconductor terminals 844, 846, establishing the electrical connectionbetween the inner conductor terminal 844, 846 and the printed circuitboard 940.

Yet another exemplary embodiment of an electrical connector 950 isillustrated in FIG. 10 c. In this embodiment, the first support element920 includes a socket 928 for receiving pin 950 operably connected tothe printed circuit board 940. The pin 950 passes through opening 935 inthe second support element 930 and through one of the inner conductorterminals 844, 846. Inner conductor terminals 844, 846 may be in theform of a conductive annulus that surrounds and is in contact with thepin 950 to establish the electrical connection.

The electrical connector 950 of the present technology is not intendedto be limited to any particular structure or device but may encompassany structure, device, or combination of structures or devices forestablishing an electrical connection between the printed circuit board940 and the substrate 800. For instance, the electrical connector mayinclude any flex wire, spring pin, spring socket, pin and socketcombination, pin and nut combination, or any other device or structure.In a particular embodiment, a fuzz button connector or interposermanufactured by Custom Interconnects may be used as the electricalconnector 950.

The present technology provides for enhanced operational and endurancecharacteristics for the tire mountable apparatus. By arranging theterminal conductors of the substrate 800 in a substantially linearrelationship, the substrate 800 may be used in accordance with thepresent technology to minimize stress applied to the conductor terminalsand various devices or components attached to the conductor terminals.The present technology also allows for multiple electrical connectionsbetween various devices or components and the substrate withoutdeviating from the various benefits provided by the 1-D tire mountableapparatus.

While the present subject matter has been described in detail withrespect to specific embodiments thereof, it will be appreciated thatthose skilled in the art, upon attaining an understanding of theforegoing may readily produce alterations to, variations of, andequivalents to such embodiments. Accordingly, the scope of the presentdisclosure is by way of example rather than by way of limitation, andthe subject disclosure does not preclude inclusion of suchmodifications, variations and/or additions to the present subject matteras would be readily apparent to one of ordinary skill in the art.

1.-13. (canceled)
 14. A method for reducing strain in a tire mountedassembly, comprising: providing a substrate defining a longitudinaldirection, a top surface and a bottom surface, the substrate comprisinga plurality of conductor terminals arranged in a substantially linearrelationship; positioning a first support element beneath the bottomsurface of the substrate so that the first support element overlaps theplurality of conductor terminals of the substrate; and positioning asecond support element above the top surface of the substrate so thatthe second support element overlaps the plurality conductor terminals ofthe substrate.
 15. The method of claim 14, comprising: positioning theconductor terminals of the substrate along a line about 80° to about100° to the longitudinal direction of the substrate; and mounting thesubstrate in a tire so that the longitudinal direction of the substrateis aligned substantially perpendicular to the direction of rotation ofthe tire.
 16. The method of claim 14, wherein the substrate comprises apiezoelectric device comprising a piezoelectric layer positioned betweena first conductor layer and a second conductor layer.
 17. The method ofclaim 14, where in the method comprises: providing a pair of first andsecond posts extending from the first support element; connecting eachof the first and second posts to one of the plurality of conductorterminals arranged on the substrate; and securing a printed circuitboard to the pair of first and second posts such that the printedcircuit board is supported above the second support element.
 18. Themethod of claim 14, wherein the method comprises providing solder at aninterface between the first support element, the second support element,and the plurality of conductor terminals.
 19. The method of claim 18,wherein the method comprises providing a compression load to theinterface between the first support element, the second support element,and the plurality of conductor terminals.
 20. The method of claim 19,wherein the method comprises providing the compression load bytightening the connection between the printed circuit board and thefirst and second posts.